I'm 100% sure that manufacturers are indeed doing that kind of research. They just find that thinner oils are "good enough," which is what matters to them.
Confessions of a Recovering Thickie
- Thread starter Hohn
- Start date
- Status
UOAs aren't good for comparing wear between different oils. UOAs test the serviceability of the oil. After 100,000 miles of 2 oils (of very different quality and/or viscosity) in identical engines with identical use, both could show consistent 1 ppm/1k miles, but one of them could have far more piston deposits, ring coking, blow-by, oil consumption, seal degradation/leaks, sludge, and varnish than the other. It could also have higher wear that won't show up in UOAs because of the range of particle size the ICP captures and some wear metals getting trapped in carbonaceous deposits as they form. Factors like magnets and bypass filters will skew results.
UOAs also cannot determine the source of wear. Copper could be bearing wear or could just merely be chelation from an oil cooler or brass fitting. Iron could be wear from rings, valvetrain, crank journals, etc... or could be from rust of an iron block. Other forms of analysis like ferrous spectroscopy could better determine these things but now you're getting well outside the scope (and cost) of a UOA.
The only way you can accurately measure wear between 2 oils is with extensively controlled conditions on a dyno with before and after measurements with a profilometer for peaks and valleys on metal surfaces (particularly cylinder walls and rings), adcole machine for measuring cam wear down to a millionth of a inch, and so on. Simulation testing like Te-77 and SRV can give a good idea of that oil's performance, alongside rust, copper corrosion, and other tests.
UOAs also cannot determine the source of wear. Copper could be bearing wear or could just merely be chelation from an oil cooler or brass fitting. Iron could be wear from rings, valvetrain, crank journals, etc... or could be from rust of an iron block. Other forms of analysis like ferrous spectroscopy could better determine these things but now you're getting well outside the scope (and cost) of a UOA.
The only way you can accurately measure wear between 2 oils is with extensively controlled conditions on a dyno with before and after measurements with a profilometer for peaks and valleys on metal surfaces (particularly cylinder walls and rings), adcole machine for measuring cam wear down to a millionth of a inch, and so on. Simulation testing like Te-77 and SRV can give a good idea of that oil's performance, alongside rust, copper corrosion, and other tests.
OVERKILL
$100 Site Donor 2021
This ^^^^^^
Recall that Valvoline 100k engine test comparing synthetic vs conventional. I remember the only real difference was the conventional had more varnish but it wasn't bad.
I thought the test was 500K
UOA's are most for trending against a baseline and overall condition of the oil.
"The presence of wear metals, such as iron, copper or tin, provides evidence of equipment wear. If the metal particles are increasing in number, it’s possible that excessive wear is taking place and the equipment from which the sample came needs to be inspected closely."
https://www.chevronlubricants.com/e...rial-machinery/interpreting-oil-analysis.html
UOA can't measure varnish, or plugged rings, but it can tell you the condition of the oil itself, which is of value. However, I'd still rather have less metals in my UOA than more but I haven't seen a statistically signficant difference in all the UOA's I've seen that would lead me to believe with 100 confidence that one oil was providing better protection than another. It's not at that level.
F1 and NASCAR teams use oil analysis and so do fleets. It's a valuable too but also limited.
Thought this was a good, clear and concise answer:
OIL ANALYSIS is an accurate way to determine oil health, oil contamination and machine wear. It is a valuable preventative maintenance tool than can help identify potential problems before a major repair is necessary, while also potentially reducing the frequencies of oil changes.
"The presence of wear metals, such as iron, copper or tin, provides evidence of equipment wear. If the metal particles are increasing in number, it’s possible that excessive wear is taking place and the equipment from which the sample came needs to be inspected closely."
https://www.chevronlubricants.com/e...rial-machinery/interpreting-oil-analysis.html
UOA can't measure varnish, or plugged rings, but it can tell you the condition of the oil itself, which is of value. However, I'd still rather have less metals in my UOA than more but I haven't seen a statistically signficant difference in all the UOA's I've seen that would lead me to believe with 100 confidence that one oil was providing better protection than another. It's not at that level.
F1 and NASCAR teams use oil analysis and so do fleets. It's a valuable too but also limited.
Thought this was a good, clear and concise answer:
OIL ANALYSIS is an accurate way to determine oil health, oil contamination and machine wear. It is a valuable preventative maintenance tool than can help identify potential problems before a major repair is necessary, while also potentially reducing the frequencies of oil changes.
Last edited:
It's possible.
dnewton3
Staff member
I have something like 32k+ UOAs in my database; the macro data I have is massive. (I've stopped counting, and stopped collecting).
I can say with the utmost clarity that vis rarely makes a difference in wear rates. Pretty much any modern engine will run between 1-2 ppm of Fe per 1k miles. Most will trend towards the lower end of that range. The other metals (Al, Pb, Cu, Cr) are going to be nearly nothing; essentially statistical noise. Fe wear, and at times Cr, will be a factor of the loading; more fuel burned such as when heavy towing will cause these to go up a bit - that's totally "normal".
There will always be exceptions to the rule; that's true. And if you're "non stock" (tuned; hot-rod) engine needs more vis, it's certainly not a bad thing to go higher in vis. I do believe that once you get lower than 20 grade, more attention must be paid in those specialized applications (hybrids, etc).
I have started to use 5w-30 in every gas engine vehicle I have; regardless what it's spec'd for. (In my case, I'm running extended OCIs with HPL PCEO).
As always, I would caution about using singular or small batch UOAs to make any wide ranging decisions regarding specific wear rates; those must be understood with a good quantity of samples so that the Stdev is well understood.
I can say with the utmost clarity that vis rarely makes a difference in wear rates. Pretty much any modern engine will run between 1-2 ppm of Fe per 1k miles. Most will trend towards the lower end of that range. The other metals (Al, Pb, Cu, Cr) are going to be nearly nothing; essentially statistical noise. Fe wear, and at times Cr, will be a factor of the loading; more fuel burned such as when heavy towing will cause these to go up a bit - that's totally "normal".
There will always be exceptions to the rule; that's true. And if you're "non stock" (tuned; hot-rod) engine needs more vis, it's certainly not a bad thing to go higher in vis. I do believe that once you get lower than 20 grade, more attention must be paid in those specialized applications (hybrids, etc).
I have started to use 5w-30 in every gas engine vehicle I have; regardless what it's spec'd for. (In my case, I'm running extended OCIs with HPL PCEO).
As always, I would caution about using singular or small batch UOAs to make any wide ranging decisions regarding specific wear rates; those must be understood with a good quantity of samples so that the Stdev is well understood.
Last edited:
Yup. People keep trying to treat these basic snapshots as the Bible or some holy writing from God.
It all comes full circle as to why we have specifications and why owners manuals recommend what they do - because we can't determine what oil is best. I think we all agree on that, especially since UOA's don't tell you much other than the condition of the oil.
There simply is no way for anyone (average consumer) to know unless you're tearing down engines. Throw your UOAs out the window. Either buy oils meeting a known spec, or take your chance the formulator knows what they're doing.
XOM can run 500 different blends a month. Valvoline can run Seq IIIH as many times as they want.
There simply is no way for anyone (average consumer) to know unless you're tearing down engines. Throw your UOAs out the window. Either buy oils meeting a known spec, or take your chance the formulator knows what they're doing.
XOM can run 500 different blends a month. Valvoline can run Seq IIIH as many times as they want.
I've heard stories that Red Line would take an existing add pack, modify it, and run it essentially in their own cars and if the engine didn't blow up and UOA's looked ok they were good to go. Throw in some additional basic bench testing and you have your oil. Now they have access to P66 so I would expect much more thorough testing.
As a couple other posters alluded to, this seems to be the greater issue for the common average daily driver. That is, a stock engine with non-severe service getting into severe service can begin to increase risk of deposits due to the oil being stressed and this begins to highlight difference in and the potential issues of oil formulation and composition, more than viscosity. But IMO
Over the last 20 years lurking here I’ve read many of the posted controlled wear studies. They all seem to follow tribology and physics. Can someone point me to a wear study that shows less wear with lower viscosity? Honest question
As a long-time Honda owner (close to 40 years) have been fortunate to have the acquaintance and friendship of several Honda Master-Certified Technicians who service our cars and been very honest and communicating about proper service. You are correct that most Honda customers follow the MM, use whatever bulk oil the dealer supplies and have little or no major issues despite the 1.5t's "problems "
I imagine that most Honda customers trade their cars a lot earlier than most here on the forum. My issue with the Honda MM is that it's an algorithm, tells you NOTHING about the actual condition of the fluids.
My wife's 2020 CRV was exclusively short-trips and at about 2400 miles on Mobil1 0w20 EP, with the MM indicating 70% life remaining, 2 different UOA's showing the oil both diluted and thinned significantly below grade viscosity. Obviously the engine type, operating conditions and usage showing that following the MM would not be wise with long-term ownership considered. Before trading it in on an HR-V with its non-turbo, port injection engine we considered the actual usage would be classified as severe. Conversations with my trusted Technician indicating that the 2.0 engine in the HR-V would be much more tolerant of this type of usage. She drives about 3k/yr. After 30 years as a Biomedical Technician working on life-support equipment, firmly believe that Pre-emptive maintenance beats reactive maintenance every time. I'd rather just change the oil rather than an endless series of UOA's. My 2023 Civic with the 1.5t now has 22k on it, using Mobil1 5W-30 EP without issues, usually 4-5k intervals, it's does more highway but gets driven more as I'm still working part-time.
Out of curiosity, if viscosity does not matter for wear rates, what is your reason for solely running 5W-30 regardless of the specification?
Edit: To clarify, what benefit does the greater viscosity have when running extended OCIs, which you indicated is you case for the 5W-30?
I think that's because engine's today don't "wear" out. In almost every case, the reason for their end of service (in the rare event they limit the life of the vehicle) comes down to a fail mode initiated by deposits-- not by wear.
In other words, if you can keep the engine clean and free of deposits, you've eliminated the most likely reason for its demise if it isn't abused or neglected.
Engines aren't wearing out. Engines are outlasting the rest of the car these days. Which raises an interesting question, why is GF-7 still using a WPD rating of only 4.6?
I had previously laughed at that Nissan GT Engine builder guy that suggested changing the oil every 3k miles, but maybe he had a point. His suggestion could have been based on deposit formation rather than wear/TBN etc. Just a thought....
I had previously laughed at that Nissan GT Engine builder guy that suggested changing the oil every 3k miles, but maybe he had a point. His suggestion could have been based on deposit formation rather than wear/TBN etc. Just a thought....
Last edited:
what is needed is more UOA from cars over 100,000 miles.
presumably up to xyz,000 miles regular oil change matters most regardless of brand, viscosity, etc. then the engine crosses the Rubicon and wear or damage from deposits increases exponentially.
Where is the Rubicon for your car? It's probably on a spreadsheet on a random corporate server.
But since none of use know the real answer, it's better to be too conservative. IMO. YMMV.
presumably up to xyz,000 miles regular oil change matters most regardless of brand, viscosity, etc. then the engine crosses the Rubicon and wear or damage from deposits increases exponentially.
Where is the Rubicon for your car? It's probably on a spreadsheet on a random corporate server.
But since none of use know the real answer, it's better to be too conservative. IMO. YMMV.
I'm a also skeptical of the idea that deposits are the main cause of engine failure. I suspect that a lot of what gets popularly attributed to deposits is plain old ring, piston and cylinder wear. I'm not saying it doesn't happen, btw.
I totally agree with you in that most cars don't get junked because the engine wears out. More often something else goes wrong that's too expensive to fix like the transmission, or some maintenance item other than oil is neglected too long.
In half the country, the problem is rust and the average car could survive until the crusher gets it on >20k oil changes.
- Status